/*******************************************************************************
 * Copyright (c) 2000, 2015 QNX Software Systems and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     QNX Software Systems - Initial API and implementation
 *     Wind River Systems   - Modified for new DSF Reference Implementation
 *******************************************************************************/

package org.eclipse.cdt.dsf.mi.service.command.output;

import java.util.ArrayList;
import java.util.List;

/**
 * GDB/MI data list regiter names response extraction.
 */
public class MIDataListRegisterNamesInfo extends MIInfo {

    String[] names;
    protected int realNameCount = 0;

    public MIDataListRegisterNamesInfo(MIOutput rr) {
        super(rr);
        names = null;
        List<String> aList = new ArrayList<String>();
        if (isDone()) {
            MIOutput out = getMIOutput();
            MIResultRecord outr = out.getMIResultRecord();
            if (outr != null) {
                MIResult[] results = outr.getMIResults();
                for (int i = 0; i < results.length; i++) {
                    String var = results[i].getVariable();
                    if (var.equals("register-names")) { //$NON-NLS-1$
                        MIValue value = results[i].getMIValue();
                        if (value instanceof MIList) {
                            parseRegisters((MIList) value, aList);
                        }
                    }
                }
            }
        }
        names = aList.toArray(new String[aList.size()]);
    }

    /*
     * Returns the register names. 
     */
    public String[] getRegisterNames() {
        
        /*
         * The expectation is that we return an empty list. The
         * constructor quarantees this so we are good here.
         */
        return names;
    }

    private void parseRegisters(MIList list, List<String> aList) {
        MIValue[] values = list.getMIValues();
        for (int i = 0; i < values.length; i++) {
            if (values[i] instanceof MIConst) {
                String str = ((MIConst) values[i]).getCString();

                /* this cannot filter nulls because index is critical in retreival 
                 * and index is assigned in the layers above. The MI spec allows 
                 * empty returns, for some register names. */
                if (str != null && !str.isEmpty()) {
                    realNameCount++;
                    aList.add(str);
                } else {
                    aList.add(""); //$NON-NLS-1$
                }
            }
        }
    }
}
